This invention relates generally to devices and methods for controlling pressure and flow in a rotating member, and more particularly to devices and method for fluid flow and pressure control to or from a roll in a web manipulating device such as a cutoff roll.
Numerous applications exist in which it is necessary to supply pressurized fluid or a suction force to a rotating member. For example, the control, manipulation, and cutting of web material upon machinery rolls can be necessary for proper transfer and processing of such materials as paper, fabric, foil, and film. The term xe2x80x9cwebxe2x80x9d as used herein and in the appended claims means any type of material (e.g., paper, composites, plastic or other synthetic material, metal, and the like) which can be found in sheet form, regardless of sheet length, width, porosity, composition, density or weight. The web material may need to be cut or perforated by one or more retractable blades upon the roll, held to the surface of the roll by a suction force, and/or expelled therefrom by jets of fluid emitting from the roll. Each such operation can require the supply of pressurized fluid or the application of vacuum to the roll from a source external from the roll. For this purpose, rotating members are typically coupled for fluid communication at one or both ends to one or more rotary unions and associated valves.
Typically, the rotary union is coupled to a rotating valve which supplies the pressurized fluid or vacuum to one or more fluid lines in the rotating roll. Where it is desirable to control the distribution of pressurized fluid or vacuum to different locations upon the rotating roll (such as where fluid pressure or vacuum is to be applied to each portion of the roll only as it passes a certain point in its rotation, or where a fraction of pressure or vacuum-actuated blades are to be selected for actuation), the rotating valve can be controlled either manually or automatically to open or close pressurized fluid or vacuum to various locations of the roll. In conventional systems where this control is desired, multiple rotary unions are connected to the valves at the ends of the rotating roll. Necessarily, each rotary union must have one or more fluid-tight seals to the valves and/or associated elements. Increased control of pressurized fluid or vacuum distribution to the various locations of the roll therefore comes at the cost of increased system size, complexity, and expense, and with increased maintenance requirements of multiple seals, rotary unions, and associated equipment. Additionally, the ability to control pressurized fluid and/or vacuum to various locations of a roll in conventional systems is fairly limited, typically preventing a user from being able to choose from a number of flow, pressure and/or vacuum patterns or regions on the roll.
In light of the problems and limitations of the prior art described above, a need exists for a valve which is capable of distributing pressurized fluid or vacuum to user-selected locations and/or one or more patterns of user-selected locations on a rotating member such as a cutoff roll, perforation roll, or vacuum roll, which is easily and quickly adjustable to change the distribution of pressurized fluid or vacuum to the user-selected locations, and which is preferably connected via a one-port rotary union to a source of pressurized fluid or vacuum in order to increase the reliability and to reduce the manufacturing and maintenance costs of the valve. Each preferred embodiment of the present invention achieves one or more of these results.
The present invention employs a rotary phase plate which acts either alone or in conjunction with a rotary union adapter and/or a roll adapter to control the supply of pressurized fluid or vacuum from a one-port rotary union to a rotating member. The rotating member can be virtually any element or assembly to or from which fluid is passed for operations performed by the rotating member, and therefore can be used in many different applications. The rotating member can be a roll used to manipulate, control, perforate, or cut a web of material as discussed above. In such an application, it is desirable to control fluid flow and pressure to one or more selected fluid lines running along the length of the roll. Particularly in cases where regularly-spaced perforations or cuts (made by retractable blades upon the roll) are desired in the web of material passing the roll, it is also desirable to control fluid flow and pressure or vacuum to patterns of fluid lines in the roll. For example, where regularly spaced-apart blades upon the roll are extended by pressurizing fluid or vacuum lines leading to each respective blade, regularly spaced web perforations or cuts are created by permitting pressurized flow or vacuum only to those lines.
The rotary phase plate in the present invention provides flow and pressure or vacuum control to user-selected lines or patterns of lines. Specifically, the rotary phase plate has a pattern of apertures therein which substantially align with preferably regularly spaced fluid lines in the end of the roll. Rotation of the rotary phase plate with respect to the roll brings certain apertures of the rotary phase plate into fluid communication with certain fluid lines in the roll, and takes certain apertures of the rotary phase plate out of fluid communication with certain fluid lines in the roll, thereby providing pressurized flow or vacuum, or removing pressurized flow or vacuum to the fluid lines in the roll. The pattern of apertures in the rotary phase plate is preferably arranged so that two or more patterns of apertures in the rotary phase plate are aligned with fluid lines in the roll at different rotational positions of the rotary phase plate with respect to the roll.
More preferred embodiments of the present invention employ at least a roll adapter or a rotary union adapter coupled to the sides of the rotary phase plate. Most preferably, the rotary phase plate is sandwiched and held between a rotary union adapter and a roll adapter. The rotary union adapter connects the rotary union to the rotary phase plate, and has a series of fluid lines running from the connection port of the rotary union to equally-spaced ports open to the rotary phase plate. The roll adapter connects the rotary phase plate to the end of the roll, and has a series of fluid lines running from equally-spaced ports corresponding to the ports of the rotary union adapter to equally spaced ports open to the fluid lines in the end of the roll. When rotation of the rotary phase plate brings apertures therein in line with two corresponding ports in the rotary union adapter and the roll adapter, fluid communication is established from the rotary union to the roll fluid line corresponding to the ports in the adapters, thereby permitting flow to or creating a vacuum in the roll fluid line. Conversely, when rotation of the rotary phase plate brings apertures therein out of line with corresponding ports in the rotary union adapter and the roll adapter, fluid communication is cut between the rotary union and the roll fluid line corresponding to the ports in the adapters, thereby ceasing flow and vacuum to the roll fluid line. In this manner, rotation of the rotary phase plate controls flow and pressure or vacuum to selected fluid lines and patterns of fluid lines in the roll. The rotary phase plate can have multiple aperture patterns to create different combinations of open lines as the rotary phase plate is rotated.
Preferably, a significant torque must be applied to the rotary phase plate to rotate it with respect to the rotary union adapter and the roll adapter. This prevents unwanted rotation of the rotary phase plate during operation of the roll. O-rings, gaskets, washers, or other sealing elements or material sealing the aperture-to-port connections between the rotary phase plate, the rotary union adapter, and the roll adapter help to prevent unwanted rotary phase plate rotation. Also, a spring-loaded ball plunger is preferably seated within either the rotary union adapter or the roll adapter, and presses against a series of detents in the rotary phase plate to further prevent unwanted rotation of the rotary phase plate. Still other types of rotation hindering devices, elements, and materials can be used with the rotary phase plate of the present invention.